Inflatable cushion for sealing off leaks in containers and pipes

ABSTRACT

A device for sealing damaged, leaking walls of containers or tubes comprises an inflatable sealing cushion which covers the site of the leak. Said cushion has a flexible counter plate 20 provided, on opposite edge regions, with fastening elements slots 24 for a clamping device surrounding the container or the tube, and an inflatable inner space 30 on the side of the flexible counter plate facing the leak and assembled with said counter plate, said space 30 being accessible from the outside through a nipple 34 and limited by at least one wall 38 and/or 40 made of a rubber-like reinforced material. The inner space 30 is annular and delimits, together with the flexible counter plate 20, a cavity 36 enclosing the leak. A passage 26 connects the inner space 30 of this cavity 36 with the outside of the sealing cushion.

BACKGROUND OF THE INVENTION

The invention pertains to a device for sealing damaged walls ofcontainers or tubes that leak. It comprises an inflatable sealingcushion which covers the site of the leak. It is provided with aflexible counter plate which on opposite edges has fasteningarrangements for a clamping device surrounding the container of thetube. It also embraces an inflatable inner space or ring on the side ofthe flexible counter plate which faces the leaking side of the tube.This space is accessible from a nipple located outside and is limited byat least one wall that is composed of a rubber-like reinforced material.

This device, designated throughout this document as a device for sealingleakages, is familiar from German Patent Document 27 45 506. In it thecounter plate has ideally the shape of a rectangle, and metal rods areinserted into the shorter ends of the rectangle. These metal rods areembraced by a reinforcing that runs in the direction of the longer sidesof the rectangle, the attachments of the clamping and reinforcing devicebeing locked to these metal rods.

When employed, the device for sealing damaged and/or leaking sections ismounted by means of the clamping and reinforcing attachments over theleaking section and secured. The inner section of the device is thenfilled with compressed air or, alternatively, a liquid under pressure Inthis way the sealing cushion acquires a greater volume and it presseswith its lower edge around the portion of the wall that surrounds theleaking section At the same time, it tightens the belts or ropes of theclamping and reinforcing device. Thus, when inflated, the device ensuresthat a sealing edge is created by the sealing device on the areas of thewall that surround the leaking section The leaking section is therebysealed off. In this way, leakages of dangerous materials from containersor tubes that have been damaged can be stopped within a relatively shorttime Subsequent damage that might result--pollution of the environmentor explosions--can thus be avoided.

U.S. Pat. No. 3,496,963 also pertains to a sealing device for tubes. Inthis device, the inflatable cushion that covers the leakage issurrounded on its outer surface by a matching piece that is constructedas a collapsible bell. This bell has a clamping device that is fittedwith a moveable/rotatable threaded bolt By tightening the attached nut,the shell can be put under pressure, whereupon the device lies snugly onthe tube. The inflatable cushion is firmly attached to its matchingpart. Essentially, this device is suited for application on cylindricalbodies, and then only for those of a certain diameter; it is unsuitablefor general container shapes, for example, containers that are hauled bysemi-trailers. One particular disadvantage of the sealing devices thatare already in use is that they are used simply to seal a leak, but donot render it possible to extract in some way or pump off the liquid orthe gas that is present at the leak site. But this is frequentlynecessary when accidents occur involving tanker loads A tanker that hasbeen thrown off its wheels often lies in such a position that access tothe actual tanker supports is not possible, access being perhaps blockedby other objects, for example, other vehicles or bridges or earthenwalls or walls of houses. It is then difficult, and sometimes evenimpossible with the means that are at one's disposal, to empty the tankthat has been sealed off by the sealing device In this way, furtherrescue attempts can be prevented or even appreciably delayed; especiallyif, for example, the tank of the vehicle that has suffered an accidentcontains a dangerous explosive liquid. The problems described hereoccur, for example, in accidents involving tankers that are transportinggasoline.

The invention addresses this problem. Its purpose is to develop thecushion that is noted in the introduction in such a way that, while thecushion still effects a good seal around the leaking section, a liquidor a gas can be pumped off or respectively discharged via the sealingcushion.

Proceeding from the cushions for sealing leaks that is noted in theintroductory remarks this task is solved by having the inner spaceconfigured as a ring. Together with the flexible counter plate, itdefines a trough or depression that surrounds the leaking section, andan access passage ensures that the inner space of this trough isconnected to the outside of the cushion for sealing leaks.

In contrast to the cushions for sealing leaks that are already known andthat are described in the introductory remarks, this cushion for sealingleaks does not contact over its total surface area the leaking sectionand the regions of the damaged walls that completely surround the leak;rather, it makes contact outside the point of leakage and fits snugly onthe damaged wall as a ring around the leak. In this way, a hollow spaceis created between the damaged wall and the cushion for sealing leakswhen the latter is placed against a damaged wall. Whereas in thecushions for sealing leaks that are already familiar, it is not possibleto create this space because these cushions are in contact over theirtotal surface area with the surface to which they are applied. Expressedin different words: the cushion for sealing leaks that is constructed inaccord with the terms of this invention lies like a bell around theleaking section. It constitutes the trough which is filled by the liquidwhich streams from the leak. Thus, the trough becomes a collecting basinfor discharged fluid, and by means of the access that is planned inaccord with this invention, the fluid that collects in the trough can beremoved.

The fact that the cushion for sealing leaks makes contact by virtue ofthe ring-shaped inner space in a ring around the leak (contact is nolonger over the total surface area), further ensures that the cushionfor sealing leaks cannot be damaged by sharp-edged sections whichcomprise the edge of the leaking section In all, the device for sealingleaks that is in accord with this invention can be employed in all thoseinstances for which the devices for sealing leaks described above couldalso be employed It can be applied simply and in very many differentsituations--even when space is severely limited--and it can be storedboth without problem and in a minimum of space. In contrast to thedevices for sealing leaks that are already known, it has the addedadvantage that it does not make contact, or makes less contact, with theedge of the leak. That allows liquid or, respectively, gas, to be drawnoff.

The term "ring-shaped" is not to be understood as delimiting solely acircle but rather every possible closed area configuration, especiallyoval ring, a rectangular ring, et cetera The size of the cushions forsealing leaks--and here there is no difference to the cushions forsealing leaks that are already known conforms to the size of thetypically occurring leak For practical application oblong-rectangularcushions for sealing leaks with the dimensions 30×60 cm have proven tobe suitable and practical By reason of the reinforcing of its walls, theinner space is so capable of withstanding pressure that, even wheninflated and applied only loosely and without bracing to a wall, it willnot burst when subjected to the maximum pressure The flexible counterplate adapts itself extensively to the curvature of the damaged wall.The clamping devices make it possible to attach it even to the externalwalls of containers, thereby ensuring that the cushion for sealing leaksdoes not, when correctly applied, slip sideways away from the leakingsection.

Two essentially different types of construction are proposed for thecushion for sealing leaks that is in accord with the invention: In thefirst version, the cushion for sealing leaks is composed of the flexiblecounter plate and an inflatable ring that is joined to this counterplate and that is constructed of reinforced rubber material which, forexample, is in the shape of a tire, but ideally is rectangular or,respectively, oval in shape In the other version, the cushion forsealing leaks is constructed of layered, hoop-shaped rubber materialthat is reinforced. The cushion for sealing leaks consists essentiallyof two walls, a cushion wall that faces away from the leak and a cushionwall that faces to the leak These walls can hang together as one pieceor can be cut separately. When cut separately, both walls of the cushionshould be reinforced in different directions so that the wall of thecushion that faces the leak can extend itself more forcefully than thewall that faces away from the leak. Both the walls of the cushion arelinked not only around the edges but also in the center where the troughis formed. Thus, when inflated, they constitute a body which resemblesan inflatable rubber boat. In such a construction, it is advantageous tomount, on the side of the cushion that faces the leak, in the region ofthe inflatable inner space, a ring-shaped seal that totally surroundsthe inner space, for example, a sealing lip or raised edge of rubbermaterial, or one or more sealing edges, and so on. They ensure that noleakages occur between the cushion for sealing leaks and the damagedwall. These leakages occur because the cushion for sealing leaks becomesstiffer when inflated and takes on its own shape, i.e., it no longer isas flexible as it was when uninflated.

In contrast to suction bells, which when applied to leaking sections ofdamaged containers or tubes, work with negative pressure, the cushionfor sealing leaks that is constructed in accord with the inventionenjoys the advantage of a higher degree of adhesive/sealing pressuresand a closed inner space The higher adhesive pressures are achieved bymeans of fill pressures which total several times--for example, sixtimes--atmospheric pressure.

Further advantages and characteristics of the invention derive from theremaining claims sought and from the following description of threetypes of the invention, these types being understood as not limiting inany way the invention. These types are described in more detail belowwith reference to the drawings.

IN THE DRAWINGS

FIG. 1 shows a perspective representation of a cushion for sealingleaks, having a ring-shaped inner space that, when inflated, is like apipe, and further has a flexible counter plate that is firmly connectedto the jacket of the inner space.

FIG. 2 shows a cross-section with altered scale along the cross-sectionII--II in FIG. 1.

FIG. 3 shows a perspective representation of a cushion for sealing leaksthat has been manufactured of reinforced material The cushion is notinflated. It has a raised sealing edge/abutment.

FIG. 4 shows a cut along the cross-section line IV--IV in FIG. 3 withthe cushion inflated.

FIG. 5 shows a cross-cut corresponding to FIG. 2 or 4 through a thirdtype that is constructed in accord with the invention.

FIG. 6 shows a cut along the cross-section line VI--VI in FIG. 3 withthe cushion deflated.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The cushion for sealing leaks that is constructed according to the firstversion shown in FIGS. 1 AND 2 has a flexible counter plate 20 that isrectangular in shape, the length being 60 cm, the width 30 cm and thethickness 15 mm. It is manufactured of reinforced rubber material,ideally rubber that has been reinforced with steel cords (46); and ithas on its opposite edge regions, which in this instance are the narrowsides 22, slots 24 which run in the direction of the narrow side andthrough which clamping straps, which have dimensions similar to thesafety belts of vehicles, can be inserted. Finally, a passage 26 isincluded in the counter plate 20. This passage transverses the counterplate 20 and has, on the side that faces away from the leak a linkingconnection 28 for attaching a pipe or a valve. The passage itself is atube with a clear internal diameter of 25 mm. This tube is constructedas a metal pipe and is so stiff under pressure that even when inflatedand in actual use it cannot be constricted or have its wall pressedtogether.

A hose-like body that defines a ring-shaped inner area 30 is firmlyattached on the main surface of the counter plate 20. The wall isconstructed of a rubber-like, reinforced by a reinforcement (48)material. In the type illustrated, it is constructed of two ring-shapedsections that are linked together in the region of a plane, seam 32,that runs parallel to the counter plate 20. It is also possible toconstruct it without a seam.

The inner space 30 is accessible via a nipple 34 that is constructed asa piece of piping It runs parallel to the plane of the counter plate 20,and is advantageous when the cushion is being used in constricted spacesand when being stored. The nipple 34 is sited in a corner section of theinner space 30. The width of the inner space 30 corresponds to thebreadth of the counter plate 20, while the length of the inner space 30is somewhat shorter than the counter plate so that the total of fourslots is accessible at all times.

The section of the counter plate 20 that remains free within the wall ofthe inner space 30--the passage 26 is sited in this region--and theparts of the walls of the inner space 30 which point inwards define atrough 36 below which, in practical application, the leaking section(not shown) of a damaged wall (also not shown) is sited.

The cushion for sealing leaks constructed according to the typedelimited in the FIGS. 3 and 4 is manufactured in one single productionprocess from a section of ribbed rubber material that was not vulcanizedbefore treatment, but that was vulcanized hot and reinforced in a press.In this cushion for sealing leaks, the flexible counter plate 20 isconstructed essentially by a cushion wall that faces away from the leak38, but also in part by a cushion wall that faces the leak 40. Boththese walls, which reveal the same rectangular dimensions, are unitedtogether not only along their rectangular sides, which is to say alongtheir edges, but also in the region of a middle rectangle. In this way,the two cushion walls 38, 40 define the ring-shaped, hose-like innerspace 30 to which attention is drawn in FIG. 4. This inner space 30 isaccessible via a nipple 34 in a manner that is well known. This nippleis sited in a corner section and runs parallel to the planes of thewalls 38, 40.

Mounted on the side of the cushion that faces the leak--in the FIGS. 3and 4 it is the upper cushion wall 40--in the vicinity, and only in thevicinity of the inner space 30 is a sealing abutment/raised lip 42. Itis sited directly on the cushion wall 40 and connected to it. In thetype of sealing cushion illustrated, it has essentially the shape of arectangular frame the length of which is somewhat shorter than thelength of both the cushion walls 38, 40. Its width corresponds to thewidth of both the cushion walls 38, 40. It has a rectangular recesswhich is so constructed that its width is approximately 8 cm. whereas inanother type of the device, its width is 4 cm. Its thickness isapproximately 4 cm. This framework sealing lip/edge 42 can beconstructed by cutting from non-reinforced rubber material--fromrecycled rubber, for example--a plate of 4 cm thick rubber so that itfits the given rectangular dimensions. From this insert a rectangle isthen cut on the inside so that a frame width remains in the givendimensions.

The passage 26 is conducted through one of the long walls of theframe-shaped sealing edges 42 This passage is also constructed as pipethat is resistant to pressure, and it runs parallel to the plane of thewalls 38, 40. When the cushion is to be employed in limited space, thisis of greater advantage than a construction that runs at an angle to thecounter plate 20 such as would be the case if the cushion were designedaccording to the first type of the device.

In a model of the device constructed in accord with FIGS. 3 and 4, thetrough 36 is limited by the side of the cushion that faces the leak 40.More specifically, it is defined by the surface over which in theirmiddle sections, the two cushion walls 38, 40 are united together and bythe inner surface of the sealing lip 42. Both the sides 38 of thecushion are joined together along their surfaces in the vicinity oftheir narrow edges, two slits 24 being incorporated once again in eachnarrow side.

The side of the cushion that faces away from the leak is reinforcedalong its long side. This is effected by, for example, steel cords whichare conducted around the edges, but especially the outer edges of theslits 24. For purposes of reinforcing a longitudinal element, forexample, a metal rod, can be incorporated between the outer edges andthe narrow edge. This rod is embraced by the reinforcing threads. Theside of the cushion 40 that faces the leak is reinforced diagonally sothat it can expand more strongly than the side that faces away from theleak 38. Instead of steel cord threads, it is possible to utilize asreinforcing aramide or equivalent tear-resistant material.

In a modified version, it is also possible to construct as a frame thesection for the side of the cushion that faces the leak. Thus, thetrough 36 to the side that faces away from the leak is delimited solelyby the side of the cushion 38. The formation of the tie between the twowalls of the cushion 38, 40 that is mounted in the middle region--it isshown in the drawing--has, however, the advantage that no problems ofsealing can occur there, for it is not necessary to effect sealing.

The third model of the device--it is shown schematically in FIG. 5--isalso constructed of two rectangular cushion walls 38, 40 that are thesame size. The cushion for sealing leaks is shown partly inflated onlyin accord with FIGS. 2 and 4.

The model constructed in accord with FIG. 5 conforms essentially to theconformation of FIGS. 3 and 4. Here, however, a sealing edge of solidmaterial is not incorporated. Rather, the sealing edge 42 is constructedof two ring-shaped sealing lips--they bear the reference number42--which are linked to the side of the cushion that faces the leak 40.The projected seal is a ring-shaped, inner sealing lip which is slightlyinclined inwards and which, with its inner surface, delimits the trough36 together with the central area of linking of both walls of thecushion 38, 40 The sealing lip that is sited externally 42 is alsoring-shaped. It is sited on the outer edge of the hose-shaped innerspace 30 and is inclined outwards. By reason of the two sealing lipsthat constitute the sealing abutment 42 a circular space 44 is delimitedwhen the cushion is applied to a wall that is to be sealed. Thiscircular space can, by virtue of the placement of the sealing lips,allow air to be conducted off to the outside when the cushion is placedagainst the damaged wall. In this way, cohesive pressure is created onthe wall that is sealed off. In an example constructed in accordancewith FIGS. 3 and 4, both the cushion walls 38, 40 are reinforced, andthe sealing lips of the sealing abutment 42 are constructed of stiff,non-reinforced rubber material. The sealing cushion that is constructedin accord with this type can, through vulcanizing under heat, bemanufactured in one single process from a suitable section orrespectively from sealing blocks that have been prepared in advance.

The passage 26 is preferably sited in a corner section, but, as isdemonstrated in the type constructed according to FIG. 3, runningparallel to the shorter rectangular side. It is important to allowsufficient material between the passage 26 and the wall of the damagedcontainer or pipe so that a proper seal can be effected at this place,for by reason of the passage 26 the sealing lip--for example--in a typeconstructed according to the FIGS. 3 and 4 is stiffened locally and isthus not as yielding as at other places. Accordingly, the passage 26, asis shown in FIG. 3, is sited if possible in the plane of the counterplate 20, which is to say at the greatest possible distance from thesurface along which the cushion for sealing leaks is applied to thedamaged wall. In a type constructed in accord with FIGS. 1 and 2, it ispossible to site the passage between the casing of the inner space 30and the flexible counter plate 20.

It has also proven advantageous to make provision for several passages,siting them, for example, in adjoining or diagonally opposite cornerregions and linking them externally via a tube/hose by means of aY-shaped section. In this way, it is possible to ensure that the innerspace 30 is virtually completely emptied.

I claim:
 1. Inflatable cushion for sealing off leaks in containers andpipes comprising a flexible counter plate that is provided on oppositeedge regions with fastening elements for a clamping device surroundingthe container or tube; an inflatable inner space of annularconfiguration, a nipple, said inflatable inner space is accessible fromoutside of the counter plate through said nipple, said inflatable innerspace is limited by at least one wall made of a rubber-like reinforcedmaterial, said inflatable inner space is arranged on the side of thesaid counter plate facing the leak and assembled with the said counterplate, said inflatable inner space and the said counter plate delimitinga trough that covers the leak; and an access passage in the inflatablecushion for removal of a fluid that collects in the said trough. 2.Inflatable cushion according to claim 1, wherein the inflatable cushionexhibits faces and the flexible counter plate and the inflatable innerspace is formed by a side of the cushion that faces the leak and a sideof the cushion that faces away from the leak, the faces of the cushionbeing constructed of reinforced, layered, rubber-like material andlinked along their edges as well as in the region of the trough so thatthe inflatable inner space is formed between the union along the edgesand the region of the trough.
 3. Inflatable cushion according to claim1, wherein the inflatable inner space is defined by a hose-liked bodythat is connected with the counter plate and that effects sealing. 4.Inflatable cushion according to claim 1, wherein a sealing lip ismounted on the side of the inflatable inner space that faces the leakwhich sealing lip is sited directly on a cushion wall and connected toit.
 5. Inflatable cushion according to claim 4, wherein the sealing liphas the shape of a rectangular frame and the access passage protrudesthrough a wall of the said frame-shaped sealing lip.
 6. Inflatablecushion according to claim 5, wherein the sealing lip is constructed ofsolid material that has essentially a square cross-section. 7.Inflatable cushion according to claim 6, wherein the sealing lip forms agutter which, in conjunction with a wall of the container or tubedefines an annular space.
 8. Inflatable cushion according to claim 1,wherein the access passage runs parallel to the counter plate. 9.Inflatable cushion according to claim 1, wherein the counter plate isrectangular in shape.
 10. Inflatable cushion according to claim 1,wherein the inflatable cushion is manufactured in a press under heatvulcanization, in one production process, from rubber material that isreinforced and ribbed, but that before the vulcanization process was notvulcanized.
 11. Inflatable cushion according to claim 1, wherein theinflatable cushion is built up through gluing from sections that hadbeen prepared accordingly from reinforced, rubber-like material. 12.Inflatable cushion according to claim 1, wherein the access passage islocated in the vicinity of a corner region of the inflatable cushion.13. Inflatable cushion according to claim 1, wherein the access passageis located in a spot of the inflatable cushion that allows ample spacebetween the access passage and a wall of the container or tube to effectsealing in this region.